Culture

As one of the most experienced archaeologists studying California's Native Americans, Lynn Gamble(link is external) knew the Chumash Indians had been using shell beads as money for at least 800 years.

But an exhaustive review(link is external) of some of the shell bead record led the UC Santa Barbara professor emerita of anthropology to an astonishing conclusion: The hunter-gatherers centered on the Southcentral Coast of Santa Barbara were using highly worked shells as currency as long as 2,000 years ago.

"If the Chumash were using beads as money 2,000 years ago," Gamble said, "this changes our thinking of hunter-gatherers and sociopolitical and economic complexity. This may be the first example of the use of money anywhere in the Americas at this time."

Although Gamble has been studying California's indigenous people since the late 1970s, the inspiration for her research on shell bead money came from far afield: the University of Tübingen in Germany. At a symposium there some years ago, most of the presenters discussed coins and other non-shell forms of money. Some, she said, were surprised by the assumptions of California archaeologists about what constituted money.

Intrigued, she reviewed the definitions and identifications of money in California and questioned some of the long-held beliefs. Her research led to "The origin and use of shell bead money in California" in the Journal of Anthropological Archaeology.

Gamble argues that archaeologists should use four criteria in assessing whether beads were used for currency versus adornment: Shell beads used as currency should be more labor-intensive than those for decorative purposes; highly standardized beads are likely currency; bigger, eye-catching beads were more likely used as decoration; and currency beads are widely distributed.

"I then compared the shell beads that had been accepted as a money bead for over 40 years by California archaeologists to another type that was widely distributed," she said. "For example, tens of thousands were found with just one individual up in the San Francisco Bay Area. This bead type, known as a saucer bead, was produced south of Point Conception and probably on the northern [Santa Barbara] Channel Islands, according to multiple sources of data, at least most, if not all of them.

"These earlier beads were just as standardized, if not more so, than those that came 1,000 years later," Gamble continued. "They also were traded throughout California and beyond. Through sleuthing, measurements and comparison of standardizations among the different bead types, it became clear that these were probably money beads and occurred much earlier than we previously thought."

As Gamble notes, shell beads have been used for over 10,000 years in California, and there is extensive evidence for the production of some of these beads, especially those common in the last 3,000 to 4,000 years, on the northern Channel Islands. The evidence includes shell bead-making tools, such as drills, and massive amounts of shell bits -- detritus -- that littered the surface of archaeological sites on the islands.

In addition, specialists have noted that the isotopic signature of the shell beads found in the San Francisco Bay Area indicate that the shells are from south of Point Conception.

"We know that right around early European contact," Gamble said, "the California Indians were trading for many types of goods, including perishable foods. The use of shell beads no doubt greatly facilitated this wide network of exchange."

Gamble's research not only resets the origins of money in the Americas, it calls into question what constitutes "sophisticated" societies in prehistory. Because the Chumash were non-agriculturists -- hunter-gatherers -- it was long held that they wouldn't need money, even though early Spanish colonizers marveled at extensive Chumash trading networks and commerce.

Recent research(link is external) on money in Europe during the Bronze Age suggests it was used there some 3,500 years ago. For Gamble, that and the Chumash example are significant because they challenge a persistent perspective among economists and some archaeologists that so-called "primitive" societies could not have had "commercial" economies.

"Both the terms 'complex' and 'primitive' are highly charged, but it is difficult to address this subject without avoiding those terms," she said. "In the case of both the Chumash and the Bronze Age example, standardization is a key in terms of identifying money. My article on the origin of money in California is not only pushing the date for the use of money back 1,000 years in California, and possibly the Americas, it provides evidence that money was used by non-state level societies, commonly identified as 'civilizations.' "

In a first-of-its-kind study, researchers discovered that light pollution leads to more than just wasted energy and washed-out starlight--it can increase the likelihood of a preterm birth by almost 13%. Laura Argys, professor of economics at the University of Colorado Denver, collaborated with scientists at Lehigh University and Lafayette College to produce this study.

Skyglow, the brightness of the night sky apart from discrete light sources such as the moon and visible stars, is one of the most pervasive forms of light pollution. When you have increased artificial brightness at night, coming from sources like streetlamps, outdoor advertising, and buildings, it reduces your ability to see the dark sky and individual stars. The study authors found that this can lead to health issues, particularly for pregnant women.

"We discovered that increased light pollution is linked to some pretty severe health challenges," said Argys. "In pregnant women, this includes a higher chance of delivering a baby with a reduced birth weight, a shortened gestational length, and an increase in preterm births."

According to the Center for Disease Control and Prevention (CDC), babies born too early have higher rates of death and disability. In 2018, preterm birth and low birth weight accounted for roughly 17% of infant deaths (deaths before one year of age).

According to study co-author and Lehigh University Professor Muzhe Yang, the biological clock in our bodies, known as circadian rhythms, are disrupted by light pollution. This, in turn, can cause sleep disorders that ultimately lead to adverse birth outcomes. Specifically, the likelihood of a preterm birth (a childbirth before 37 weeks) could increase by approximately 12.9% as a result of increased nighttime brightness.

"While greater use of artificial light at night (ALAN) is often associated with greater economic prosperity, our study highlights an often-neglected health benefit of 'darkness,'" said Yang. "The biological clock of a human body, like all lives on the earth, needs the 'darkness' as part of the light-dark cycle in order to effectively regulate physiological functions, such as sleep."

Argys and her team hope this research stimulates policy discussions when addressing light pollution regulations moving forward.

"While beneficial to the economy and society, ALAN's consequences are evident," said Argys. "Our study has important policy implications such as why we should minimize skyglow that is, for example, contributed by streetlights."

Aging and lifestyle-related metabolic imbalances, such as hyperglycemia, hyperlipidemia, and oxidative-stress, cause the accumulation of advanced glycation end products (AGEs), including pentosidine (PEN, crosslinked type) and carboxymethyl-lysine (CML, non-crosslinked type). Osteoporosis is a widespread metabolic skeletal disease characterized by diminished bone mineral density (BMD) or bone strength, which increases the risk of fractures.

To date, the association of PEN and CML with osteoporotic fracture has been reported, and the accumulation of AGEs in bone tissue is thought to contribute to bone vulnerability via the deterioration of bone matrix proteins, especially collagen. However, the precise mechanisms of PEN and CML in fracture occurrence are unclear and remain controversial, while no studies to uncover why CML associates with fractures have been attempted. There have been no reports investigating the implications of both PEN and CML on bone metabolism, BMD, and fractures in the same patients.

Accordingly, a team of doctors from the Department of Orthopaedic Surgery, Shinshu University School of Medicine et al. examined the levels of urinary PEN and serum CML to assess and compare the impacts of those AGEs on bone status and prevalent osteoporotic fractures in a cohort of postmenopausal women.

The group found that PEN as well as CML was significantly associated with prevalent vertebral fracture in postmenopausal women. The mechanism of PEN might be independent of lumbar BMD, while that of CML could be BMD dependent. It would appear that PEN, a crosslinked type of AGE, associated independently with the occurrence of fracture via collagen network deterioration, leading to impaired bone quality without affecting BMD. On the other hand, as a non-crosslinked type of AGE, CML could have contributed to fracture occurrence through lowered BMD. Both AGEs therefore appear to impact bone status and health, although possibly via different mechanisms.

Corresponding author of the study, Associate Professor Yukio Nakamura states, this study assessed the impacts of both PEN and CML on a number of bone turnover-related markers, BMD, and fractures in the same postmenopausal outpatients who visited a primary care institution and demonstrated possible different mechanisms of those AGEs for the occurrence of fracture. Since this investigation was just a cross-sectional study, the team could not identify a causal relationship of AGEs with osteoporotic fractures.

Therefore, the pathophysiological importance of AGEs in fractures requires confirmation by a longitudinal prospective study design with general population, such as community-dwelling participants. Together with the laboratory experiments, we would like to uncover the epidemiologic and mechanistic associations between AGEs and fractures.

Finally, the team hopes to provide an effective intervention for the AGEs accumulation in bone tissue leading to bone health retention in the elderly.

Cambridge, Massachusetts - They may be the youngest astronomers to make a discovery yet.

This week, 16-year-old Kartik Pinglé and 18-year-old Jasmine Wright have co-authored a peer-reviewed paper in The Astronomical Journal describing the discovery of four new exoplanets about 200-light-years away from Earth.

The high schoolers participated in the research through the Student Research Mentoring Program (SRMP) at the Center for Astrophysics | Harvard & Smithsonian. Directed by astrochemist Clara Sousa-Silva, the SRMP connects local high schoolers who are interested in research with real-world scientists at Harvard and MIT. The students then work with their mentors on a year-long research project.

"It's a steep learning curve," says Sousa-Silva, but it's worth it. "By the end of the program, the students can say they've done active, state-of-the-art research in astrophysics."

Pinglé and Wright's particular achievement is rare. High schoolers seldom publish research, Sousa-Silva says. "Although that is one of the goals of the SRMP, it is highly unusual for high-schoolers to be co-authors on journal papers."

With guidance from mentor Tansu Daylan, a postdoc at the MIT Kavli Institute for Astrophysics and Space Research, the students studied and analyzed data from the Transiting Exoplanet Survey Satellite (TESS). TESS is a space-based satellite that orbits around Earth and surveys nearby bright stars with the ultimate goal of discovering new planets.

The team focused on TESS Object of Interest (TOI) 1233, a nearby, bright Sun-like star. To perceive if planets were orbiting around the star, they narrowed in on TOI-1233's light.

"We were looking to see changes in light over time," Pinglé explains. "The idea being that if the planet transits the star, or passes in front of it, it would [periodically] cover up the star and decrease its brightness."

To the team's surprise, they discovered not one but four planets orbiting around TOI-1233.

"I was very excited and very shocked," Wright says. "We knew this was the goal of Daylan's research, but to actually find a multiplanetary system, and be part of the discovering team, was really cool."

Three of the planets are considered "sub-Neptunes," gaseous planets that are smaller than, but similar to our own solar system's Neptune. It takes between 6 and 19.5 days for each of them to orbit around TOI-1233. The fourth planet is labeled a "super-Earth" for its large size and rockiness; it orbits around the star in just under four days.

Daylan hopes to study the planets even closer in the coming year.

"Our species has long been contemplating planets beyond our solar system and with multi-planetary systems, you're kind of hitting the jackpot," he says. "The planets originated from the same disk of matter around the same star, but they ended up being different planets with different atmospheres and different climates due to their different orbits. So, we would like to understand the fundamental processes of planet formation and evolution using this planetary system."

Daylan adds that it was a "win-win" to work with Pinglé and Wright on the study.

"As a researcher, I really enjoy interacting with young brains that are open to experimentation and learning and have minimal bias," he says. "I also think it is very beneficial to high school students, since they get exposure to cutting-edge research and this prepares them quickly for a research career."

The SRMP was established in 2016 by Or Graur, a former postdoctoral fellow at the Center for Astrophysics |Harvard & Smithsonian. The program accepts about a dozen students per year with priority given to underrepresented minorities.

Thanks to a partnership with the City of Cambridge, the students are paid four hours per week for the research they complete.

"They are salaried scientists," Sousa-Silva says. "We want to encourage them that pursuing an academic career is enjoyable and rewarding--no matter what they end up pursuing in life."

An international joint research team from the Shanghai Advanced Research Institute of the Chinese Academy of Sciences, along with Zhejiang University and the Technical University of Denmark, reported an in-situ strategy to manipulate interfacial structure with atomic precision during catalytic reactions. Results were published in the latest issue of Science.

The interface between nanoparticles and substrates plays a critical role in heterogeneous catalysis because most active sites are located at the perimeter of the interface. It is generally believed that this interface is immobile and unchangeable, thus can hardly be adjusted in reactive environments. As a result, it has been challenging to promote catalytic activity through precise control of the interfacial structure.

In this study, the scientists first used environmental transmission electron microscopy to directly visualize the epitaxial rotation of gold nanoparticles on titanium dioxide (TiO2) surfaces during CO oxidation at the atomic level. A perfect epitaxial relationship was observed between Au nanoparticles and TiO2 (001) surfaces under an O2 environment in real time.

Theoretical calculations including density functional theory calculations and thermodynamics analysis were then carried out, indicating that the epitaxial orientation could be induced by changing O2 adsorption coverage at the perimeter interface. The Au nanoparticle was more stable with adsorption of more O2 molecules at the Au-TiO2 interface, but became less stable with the consumption of O2 with CO.

To exploit the promoted activity of Au-TiO2 interface, researchers conducted additional top-view observations and found that this configuration remained unchanged when cooling from 500 °C to 20 °C in CO and O2 reactive environments, showing the rotation of the Au nanoparticle was also temperature dependent in reaction conditions.

Taking advantage of the reversible and controllable rotation of the Au nanoparticle, the scientists achieved in-situ manipulation of the active Au-TiO2 interface at the atomic level by changing gas and temperature.

This study sheds light on real-time manipulation of catalytic interface structure in reaction conditions at the atomic scale, which may inspire future approaches to real-time design of the catalytic interface under operating conditions.

Clear rules for engineering transgenes that can be inserted and propagated over multiple generations of nematodes include ways to protect inserted genes from the organism's natural defenses against foreign DNA. Developed by KAUST researchers, the rules have implications for many research fields, including gene therapy development.

Scientists often study biological processes, such as normal and mutant gene functions, in the worm Caenorhabditis elegans because it has many genes and molecular pathways in common with humans. Specific gene functions can be investigated by injecting DNA into the worm's reproductive organs, where it links into what is known as an extra-chromosomal array. This array is eventually incorporated into the nucleus, where it is duplicated and segregated into daughter cells. The injected genetic material is then potentially inherited across generations, which last only two days in C. elegans, allowing researchers to study gene functions over multiple generations in a short time period.

But C. elegans, like other multi-cellular organisms, has silencing mechanisms for recognizing and shutting down foreign DNA, which can hinder research efforts.

Scientists recently discovered that a class of noncoding DNA, called periodic A/T clusters (PATCs), can watermark their own genetic sequences to protect them from the natural silencing mechanisms of cells.

Bioengineer Christian Frøkjær-Jensen conducted investigations with students and researchers in his lab to develop rules for using PATCs, some gene regulators and reagents for persistent expression of transgenes in the C. elegans germline from simple extra-chromosomal arrays.

The protocol helps optimize transgenes and describes where PATCs should be inserted and the temperatures most suitable for propagating transgene strains, among other rules.

"Think of electrical circuits," says Frøkjær-Jensen. "Any electrical engineer can buy resistors and capacitors and be certain that these parts will behave in predictable ways when put together into a circuit. Our work aims to develop similar standards for genetic engineering in multicellular organisms. We also aim to freely distribute the necessary reagents for this process to the rest of the academic scientific community; we hope this will put KAUST on the map for biological engineering and synthetic biology."

Their investigations also led to the development of a web-based application for researchers to analyze their own DNA sequences for PATC watermarks. "PATCs can span large distances and rely on patterns that are not easily identifiable," explains Frøkjær-Jensen. "Previously, researchers needed to install specialized software to do this. Now, scientists can simply copy-paste their sequence files into our application to get an immediate analysis and graphical output." This will help scientists more easily use PATCs in their research and study their roles.

A team led by Prof. SU Bing from the Kunming Institute of Zoology (KIZ) of the Chinese Academy of Sciences (CAS), Prof. LI Cheng from Peking University, and Prof. ZHANG Shihua from the Academy of Mathematics and Systems Science of CAS has reported the highest resolution by far of the 3D genome of the primate brain, and demonstrated the molecular regulatory mechanisms of human brain evolution through cross-species multi-omics analysis and experimental validation. The study was published in Cell.

The unique pattern of human brain development stems from accumulated genetic changes during human evolution. Among the huge number of diverging genetic changes, only a small portion of the between-species changes have been functionally important. The challenge is to identify the causal changes responsible for the unique pattern of human brain development and their regulatory mechanisms. Macaque monkeys, genetically similar to humans, are the ideal model for studying the origin and developmental mechanisms of the human brain.

The genome of mammalian species including humans is about two meters long and is compiled in the nucleus with a diameter of only 10 micrometers. This nonrandom compilation is characterized by organized three-dimensional (3D) distribution, which is important for cell proliferation and differentiation during development. Recently, the invention of whole-genome chromosomal structure capture technology (referred to as Hi-C) provides a great opportunity for dissecting the fine-tuned organization of the genome during brain development.

In this study, the researchers conducted cross-species analyses of brain 3D genomes through cross-disciplinary collaboration.

They first constructed a high-resolution 3D chromatin structure map of the macaque fetal brain using the Hi-C technique. Reaching a 1.5 kb resolution, this Hi-C map represents the highest resolution of primate brains so far achieved, and it has become a useful omics dataset for revealing the 3D genome organization in detail. Meanwhile, the researchers generated a transcriptome map, a chromatin open region map and a map of the anchor protein CCCTC-binding factor (CTCF).

Based on these multi-omics data, the researchers constructed for the first time a fine map of the chromatin structure of the macaque fetal brain and identified the chromatin structure in different scales, including compartments, topologically associating domains (TADs) and chromatin loops. They also identified regulatory elements in the genome such as enhancers.

Using published human and mouse brain Hi-C data, they then performed a cross-species comparisons, and discovered many human-specific chromatin structural changes, including 499 human-specific TADs and 1266 human-specific loops. Notably, the human-specific loops were shown to be enriched with enhancer-enhancer interactions, representing the origin of a mechanism for fine-tuning brain development during human evolution.

Based on the analysis of single-cell transcriptome data on human brain development, the researchers observed that these human-specific loop-related genes are highly expressed in the subplate lamina, a transient zone of the developing brain critical for neural circuit formation and plasticity. The subplate lamina had been found to show an extradentary expansion compared to that of the macaque and mouse, and is about four times the thickness of the cortical plate. The subplate starts to decrease after birth and eventually disappears, and little is known about this transient zone. This finding provides the first evidence for the key role of the subplate in forming human-specific brain structures during development.

In addition, the researchers discovered that many human-specific mutations (e.g., point mutations and structural changes) are located in the TAD boundary and loop anchor regions, which may lead to the origin of novel binding sites of transcriptional factors and human-specific chromatin structures.

The researchers studied an example involving the EPHA7 gene, which is highly expressed in the subplate and is critical for neuronal dendrite development. The human-specific point mutations of EPHA7 lead to the formation of human-specific enhancers and loops. Through an experiment involving enhancer knockout in cell lines, they proved that human-specific EPHA7 enhancers can cause regulatory changes in EPHA7 expression and affect dendrite development.

This study sheds new light on the genetic mechanisms of human brain origin and serves as a valuable resource for 3D brain genomes.

Advances in DNA sequencing have uncovered a rare syndrome which is caused by variations in the gene SATB1.

The study, co-authored by academics from Oxford Brookes University (UK), University of Lausanne (Switzerland), Radboud University (The Netherlands), University of Oxford (UK), University of Manchester (UK) and led by Max Planck Institute for Psycholinguistics (The Netherlands), discovered three classes of mutations within the gene SATB1, resulting in three variations of a neurodevelopmental disorder with varying symptoms ranging from epilepsy to muscle tone abnormalities.

Recognition of disorder will increase understanding and diagnosis

An international team of geneticists and clinicians from 12 countries identified 42 patients with mutations in the gene SATB1 who were all displaying a range of similar symptoms, albeit of varying severity.

Variations, or mutations, of SATB1 were found to have different effects in the cell. For example, some variations led to increased activity of the protein which causes a more severe type of disorder, while other variations cause loss of function of the gene and lead to less severe difficulties.

The SATB1-syndrome is characterised by neurodevelopmental delay, intellectual disability, muscle tone abnormalities, epilepsy, behavioural problems, facial dysmorphism and dental abnormalities.

Dr Dianne Newbury, Senior Lecturer in Medical Genetics and Genomics at Oxford Brookes University said: "Previously, just one or two cases of patients with SATB1 variations had been described but it was not recognised as a specific syndrome. Patients displaying these characteristics and their families, will have known that they had an undefined neurological condition, but they wouldn't have known any specific detail about the condition, or why they had it.

"We hope that the recognition of this new disorder, and the information about the molecular pathways contributing to it, will help the families and individuals affected understand more about the condition and achieve a diagnosis they would not have had previously."

Three classes of mutation have different effects in the cell

The mutations found in the genome of the patients were found to belong to three different classes. The first mutation class, identified in eight patients, caused a loss of function of the SATB1 gene and halved the production of the encoded protein. This leads to a less severe syndrome characterised by diminished cognitive function, visual problems and facial dysmorphism.

The second class contains four mutations, which encode shorter proteins that are less efficient as they are not positioned correctly in the cell. This second mutation shows as an intermediary syndrome, characterised as more severe than the first, but less severe than the third.

The third class of variation encompasses the mutations found in the last thirty patients. These modify the encoded protein, making it more active. This altered protein is 'sticky' and binds better to DNA, diminishing the expression of genes it regulates and causing a more severe type of disorder, characterised by severe intellectual disability, epilepsy, a motor speech disorder (dysarthria) and specific facial features.

Understanding mutations is key to discovering the origin of genetic diseases

Dr Alexandre Reymond, Director of the Center for Integrative Genomics at the University of Lausanne in Switzerland said: "These results demonstrate that each mutation is different and that is essential to understand their mode of action in order to explain the origin of genetic diseases.

"We must go beyond sequencing, which is only a first step."

Skoltech scientists have developed an algorithm that can identify various tree species in satellite images. Their research was published in the IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing.

Identifying tree species is essential for efficient forest management and monitoring. Satellite imagery is an easier and cheaper way to deal with this task than other approaches that require ground observations of vast and remote areas.

Researchers from the Skoltech Center for Computational and Data-Intensive Science and Engineering (CDISE) and Skoltech Space Center used a neural network to automate dominant tree species' identification in high and medium resolution images. A hierarchical classification model and additional data, such as vegetation height, helped further enhance the predictions' quality while improving the algorithm's stability to facilitate its practical application.

"Commercial forest taxation providers and their end-users, including timber procurers and processors, as well as the forest industry entities can use the new technology for quantitative and qualitative assessment of wood resources in leased areas. Also, our solution enables quick evaluations of underdeveloped forest areas in terms of investment appeal," explains Svetlana Illarionova, the first author of the paper and a Skoltech PhD student.

There are plans to integrate the developed algorithms in the Geoalert platform to automate the production of forest engineering materials marketed via Parma-GIS.

Thursday, 28 January 2021: A study has found that adolescents who frequently use cannabis may experience a decline in Intelligence Quotient (IQ) over time. The findings of the research provide further insight into the harmful neurological and cognitive effects of frequent cannabis use on young people.

The paper, led by researchers at RCSI University of Medicine and Health Sciences, is published in Psychological Medicine.

The results revealed that there were declines of approximately 2 IQ points over time in those who use cannabis frequently compared to those who didn't use cannabis. Further analysis suggested that this decline in IQ points was primarily related to reduction in verbal IQ.

The research involved systematic review and statistical analysis on seven longitudinal studies involving 808 young people who used cannabis at least weekly for a minimum of 6 months and 5308 young people who did not use cannabis. In order to be included in the analysis each study had to have a baseline IQ score prior to starting cannabis use and another IQ score at follow-up. The young people were followed up until age 18 on average although one study followed the young people until age 38.

"Previous research tells us that young people who use cannabis frequently have worse outcomes in life than their peers and are at increased risk for serious mental illnesses like schizophrenia. Loss of IQ points early in life could have significant effects on performance in school and college and later employment prospects," commented senior author on the paper Professor Mary Cannon, Professor of Psychiatric Epidemiology and Youth Mental Health, RCSI.

"Cannabis use during youth is of great concern as the developing brain may be particularly susceptible to harm during this period. The findings of this study help us to further understand this important public health issue," said Dr Emmet Power, Clinical Research Fellow at RCSI and first author on the study.

The study was carried out by researchers from the Department of Psychiatry, RCSI and Beaumont Hospital, Dublin (Prof Mary Cannon, Dr Emmet Power, Sophie Sabherwal, Dr Colm Healy, Dr Aisling O'Neill and Professor David Cotter).

The research was funded by a YouLead Collaborative Doctoral Award from the Health Research Board (Ireland) and a European Research Council Consolidator Award.

Investors' moods are affected by gloomy weather. New research from Copenhagen Business School recommends entrepreneurs looking for finance should be aware of the weather forecast at the time they want to launch their crowdfunding campaigns.

The researchers wanted to explore whether weather-induced moods can explain crowdfunders' contributions and focused on the role of investors' moods and emotions including day-to-day decisions on the crowdfunding platform Companisto.

"Financial investment plays a vital role in the success of an entrepreneurial venture and our research shows that on cloudy days, funders invest between 10-15% less money in risky equity crowdfunding campaigns," says Assistant Professor Ali Mohammadi from Department of Strategy and Innovation, Copenhagen Business School.

"We also show there is no differences between male and female investors and find that novice investors react more to the gloomy weather," adds Mohammadi.

The research is published in the Journal of Corporate Finance with co-author Kourosh Shafi, Assistant Professor of Entrepreneurship, California State University East Bay, Hayward, CA, USA.

Mood fluctuations

This research complements existing evidence on the link between weather as a mood stimulus and outcomes in various financial markets but what is different here is the focus on equity crowdfunding.

The quantitative research data came from the German company Companisto, one of the largest European equity crowdfunding platforms and consisted of examining 102 campaigns which received 67,982 pledges. This allowed the researchers to observe the city of where the investor lived and allowed them to link the weather data to the investor and the exact day of each investment.

"The weather measure is simply cloud coverage, which varies from no cloud at all (0) to completely cloudy (1). Hence, we can see weather fluctuation for the same campaign during the fundraising period. This setting allows us to isolate the effect of weather from effect of entrepreneur and investor characteristics. What is interesting about mood is that it is not directly related to economic value or return of an investment," adds Assistant Professor Mohammadi.

Maximise fundraising success

While entrepreneurs cannot fully predict the weather to strategically time the campaign launch to maximise fundraising success, there are a number of strategies the researchers recommend that could be considered to offset the adverse effects of cloudy days.

"These include targeting more experienced investors and engaging in campaigns at a later stage of venture development if possible. On cloudy days, entrepreneurs can also increase their marketing activities in ways that reduce the negative effect of weather," concludes Mohammadi.

Researchers at Lund University in Sweden believe they have identified a gene variant that can cause cerebral small vessel disease and stroke. The study is published in Neurology Genetics.

"The patients we have studied are from the same extended family, and several of them have been diagnosed with cerebral small vessel disease and suffered strokes. After tissue examination and using genetic sequencing methods, we found that they were carriers of a new gene variant that could be connected to their diagnoses," says Andreea Ilinca, researcher at Lund University and neurologist at Skåne University Hospital.

Stroke is either caused by a blood clot that leads to a lack of oxygen in the brain, or a hemorrhage in the brain. High blood pressure, high cholesterol levels, diabetes, atrial fibrillation and lifestyle factors such as smoking are known risk factors for stroke. However, an increasing amount of research is indicating that genetic factors also play a major role.

Therefore, the Lund researchers have studied an extended family, the majority of whom live in southern Sweden, where eight out of 15 people developed cerebral small vessel disease. The disease is characterized by ischemic stroke (cerebral infarction caused by blood clots) and cerebral hemorrhage, as well as mild cognitive impairment, autonomic nervous system dysfunctions and coordination difficulties.

When examining tissue from those that had experienced symptoms, the researchers could see microscopic changes in the blood vessels of the brain and in small skin vessels.

Using modern genetic analysis methods, they were also able to establish that they had found a new variant in the MAP3K6 gene, that they believe may be related to the disease. MAP3K6 is a gene that, among other things, affects the function of a protein that helps the brain's blood vessels to react correctly to damage, such as a low oxygen supply to the brain.

"By identifying genetic variants that are associated with disease in the vessels of the brain and early stroke, we can better understand what could prevent these harmful processes. Future studies that can give us more knowledge about the molecular disease mechanism can lead to new treatments", concludes Andreea Ilinca.

Paris, France, January 27th 2021 -- COVID-19 vaccine distribution has begun across the globe, while many countries are still struggling with the rampant rise of infections. Owkin, a French-American startup pioneering AI and Federated Learning in medical research, has been focusing it's COVID-19 research efforts on aspects of the pandemic that still require much public health attention, despite the arrival of an effective vaccine.

Efforts to support frontline health systems as they devote their resources to the influx of COVID-19 related hospitalizations, have resulted in the AI-Severity Score, published in Nature Communications this week . This machine learning model, trained on multimodal data sets that include CT scans of the lungs (a routine procedure upon admission), is plug and play and able to predict the severity of a patient's disease prognosis with a performance that surpasses all other currently published score benchmarks. Use of these scores supports hospital resource management and planning, a sometimes overlooked function that, when managed well, saves lives. This research was made possible through a consortium, called ScanCovIA, made up of Institut Gustave Roussy, Kremlin-Bicêtre APHP, Owkin, and Digital Vision Center of CentraleSupélec and INRIA.

Additionally, Owkin has been developing other machine learning models to discover more coronavirus epitopes that are most likely to be effective in future vaccines As the virus continues to mutate, we don't yet know how long the current vaccines will remain efficacious or if, like the flu, they will require annual or semi annual development. Furthermore, it may be possible to develop vaccines for genes within the virus's DNA that are more stable, and less likely to mutate. Epitope prediction can speed vaccine development by narrowing the field of epitopes to test in the lab, and it can diversify our defenses against the virus's future mutations. Furthermore, these models can be deployed outside vaccine research; they can also be used in oncology research. The ultimate aim of machine learning for epitope discovery is to have a better understanding of the immune response--these features of the model have their place across the spectrum of precision medicine research.

The main culprit in cancer is healthy cells that have gone rogue and acquire the ability to divide uncontrollably. These cells acquire growth advantages over normal cells and manipulate their environment by altering the cellular pathways involved in growth and metabolism. Over the past few decades, various altered pathways and proteins have been identified as targets for therapeutic interventions. However, what remains challenging is selectively targeting cancer cells and ensuring that the drug reaches the tumor in adequate amounts, without severely affecting normal cells. And in this regard, biocompatible delivery vehicles (which are non-toxic to normal cells) can be useful.

One such potential candidate is "porphyrins," a group of organic cyclic compounds that form the functional center of several proteins in the human body. Porphyrins are known for their "photosensitizing" effects, that is, their ability to release reactive oxygen species upon light stimulation. These reactive species are what gives porphyrins their anticancer activity. Porphyrins have another advantage: structurally, they are composed of four subunits called "pyrrole subunits," which give them specific electronic properties. These electronic properties, in combination with receptors on cancer cells, facilitate the selective accumulation of porphyrins in cancer cells, thereby serving as an effective drug delivery system. But how the steric position (atomic arrangement) of the functional groups bound to porphyrins favors maximum accumulation and distribution of porphyrin-conjugated drugs in cancer cells hasn't been well studied.

To answer this question, researchers at Tokyo University of Science, including Asst. Prof. Toshifumi Tojo, Mr. Koshi Nishida, Assoc. Prof. Takeshi Kondo, and Prof. Makoto Yuasa, dug deeper into how the structure of porphyrin derivatives can affect tumor accumulation. Their findings are published in the journal Scientific Reports. Explaining their motivation, Dr. Tojo, who led the study, says, "Porphyrins are used as the basic skeleton of new drugs for cancer treatment due to their ability to accumulate in cancer cells. They possess different functional group modification positions for drug conjugation. Whether these positions confer different physical properties and membrane permeability remains unclear. Our aim was to investigate how these differences impact drug delivery."

In their study, the researchers explored the β (third) and meso (middle) position of functional groups in porphyrins. First, using a breast cancer cell line, they looked into how these functional positions affect the time-dependent accumulation in cancer cells, ranging from 2- to 24-hour time points. They found that meso-derivatives accumulated in cells at 3-fold higher amounts than β-derivatives and that derivatives with smaller functional groups allowed better aggregation than the larger ones.

Next, they investigated how these functional group positions influence the pathway by which porphyrins enter cancer calls. They found that porphyrin conjugates form complexes with plasma proteins that facilitate their transport via endocytic vesicles. Additionally, the compounds could also diffuse into the cytoplasm through the cell membrane.

Moreover, considering their electron-rich nature, porphyrins likely interact with serum proteins that transport them to the cells. The researchers, therefore, measured how different positions influence the affinity of these porphyrin conjugates with serum proteins and how increased affinity may enhance tumor accumulation. They found that while the meso-position improves intracellular accumulation of porphyrin conjugates, it did not have a major effect on the movement of small functional groups into the cell.

Concluding their findings, Dr. Tojo remarks, "Our study reveals that the functional group modification position of porphyrin greatly affects the membrane permeability and intra-cellular tumor accumulation. We are hopeful that our findings can help inform guidelines for the structural design of novel porphyrin drugs."

Overall, their study gives insight into how the structure of drug delivery systems like porphyrins must be considered to achieve maximum efficacy, hopefully paving the way for advancements in cancer drug delivery.

An international team of researchers led by the Universities of Liverpool and Keele, working with Public Health England, has found that the common anticoagulant drug heparin inhibits the SARS-Cov2 virus spike protein, by reducing the virus' ability to attach to human cells and infect them.

The research, published in the journals British Journal of Pharmacology, and Thrombosis and Haemostasis, found that heparin interacts with the spike protein on the surface of coronavirus (SARS-CoV2), destabilising its structure and preventing it from docking with the ACE2 receptor on human cells.

Molecular modelling by collaborators at Queensland University in Australia showed how heparin can stick to the surface of the spike protein to achieve these effects, and studies with live SARS-CoV2 virus carried out at Public Health England's Porton Down laboratory showed that unfractionated heparin (but not low molecular weight heparins) could inhibit cell infectivity at doses similar to those currently used in clinical settings as an anticoagulant.

Crucially, the data strongly supported the clinical testing of inhaled ("nebulised") unfractionated heparin, since the doses known to be delivered to the lungs would have very strong anti-viral effects.

Professor Jeremy Turnbull from the Department of Biochemistry and Systems Biology at the University of Liverpool said: "This is exciting news since heparin could be rapidly repurposed to help alleviate Covid-19 infections, or possibly as a prophylactic treatment for high-risk groups such as medical staff or care workers. The results have also led us to investigate other novel compounds which mimic heparin that could potentially be effective against SARS-CoV2."

Dr Mark Skidmore from the School of Life Sciences at Keele University co-led the research. He said: "We also know that heparins inhibit a range of other viruses, so studying these drugs could provide new therapeutic strategies, and possibly a first-line of defence against emerging viral threats in the future, for example while vaccines are developed."

Professor Miles Carroll, of the National Infection Service, Public Health England added: "New treatments which target the SARS-CoV2 virus are urgently needed. Heparin, with its well-known clinical safety profile, is certainly an interesting candidate for repurposing against Covid-19."

"The Covid-19 pandemic has had a significant impact on the delivery of NHS services and local communities. These results strengthen the need for further investigation of heparin as a treatment in Covid-19 patients," said Dr Quentin Nunes, Consultant at the East Lancashire Hospitals NHS Trust, who is leading efforts to begin clinical trial of nebulised heparin in ITU patients in the UK.

The early release of preprint data from this study in March 2020, now published in peer-reviewed journals, has stimulated international efforts to explore the use of heparins for Covid-19 treatment. Further work is now ongoing to explore the potential of heparin and heparin-mimicking compounds as potential broad-spectrum antiviral drugs for Covid-19 and other emerging viral threats.